Cadillac Repair Questions? Ask a Mechanic for Answers ASAP
I am sorry that you have not been helped yet. I just came online and saw your question
How long does it hold pressure with key on engine off, and key off?
Is the spark bright blue when it is hard to start or wont start?
What is the rpm cranking signal look like on the no start?
Please remember that I am not there to test anything and rely on you for as much detail as possible
did you replace the whole fuel pump module or just the pump motor itself
Sounds like it is a defective pump but I will opt out and see if another expert has any other ideas
If this problem was there before the new fuel pump, I doubt if that is it. If it was there before and the new pump didn't help and there are no codes and also it starts with starting fluid " insint start", I assume that is what that meant, then perhaps the fuel injector pulse is just off somewhat and the engine is flooding. I would reprogram the ecm/pcm with the latest software and try that.
Well, that was my 2 cents worth. You should have mentioned that but anyhow, I will opt out now, too. Maybe another expert has something eels to add.
Hi my name is ***** ***** I will be happy to assist with this today.In some cases I may need more info to assist better.I apologize for any delay.
Do you smell fuel at all when this hard start occurs when the engine is hot or cold on the inside or outside of the vehicle especially at the exhaust?
Let me know so we can continue,thanks Pete.
When the fuel pump was replaced did you check the fuel pump connection for any corrosion at any of the terminals or damaged/corroded wiring at the connection?
O.k.,you shouldnt see the pressure drop below 50 psi so the low (47 psi) of pressure is causing this here.Since the pump is new and this was also an issue with the old pump pressure the pump isnt the cause here.
I suspect you have a low voltage or ground issue to the pump when it heats up causing the low pressure issue.This is most common with poor connections at the pump itself or a fault with the ground that feeds the pump.The ground for the pump comes in on the black wire in terminal A at the pump.This black wire connects to ground G300.
G300 is located on the frame rail near the fuel tank as seen here.Make sure it is clean and tight and remove it and clean the area.Clean the battery ground as well as where the ground leads to from the battery to see if this corrects this issue here.
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